1. Technical Field
The present invention relates to a cell processing apparatus, a sample preparation apparatus, and a cell analyzer.
Specifically, the present invention relates to a technique for easily collecting a measurement target cell that is discriminated by a filter from other cells.
2. Background Art
Conventionally, as a cell analyzer for analyzing cells included in a biological sample extracted from a living body, there has been known a cell analyzer in which epidermal cells of a cervix included in a sample extracted from the cervix of a subject are measured by a flow cytometer to perform the screening of cancer cells and atypical cells (e.g., see the pamphlet of International Publication No. 2006/103920).
In the case of the cell analyzer disclosed in the above pamphlet, an epidermal cell of a cervix is assumed as a measurement target. A sample extracted from a cervix includes not only an epidermal cell but also cells such as red blood cells and white blood cells. If the sample is measured without any processing, the measurement result is influenced by the cells such as red blood cells or the white blood cells. This may prevent an accurate screening of cancer and atypical cells.
Thus, there has been required a technique for discriminating a measurement target cell and cells other than the measurement target cell to easily collect only the measurement target cell.
As a technique for performing the above collection, a cell separation/collection apparatus has been known for example in which cell suspension liquid including blood cells is allowed to flow on a filter and a lymphocyte as a measurement target cell is captured by the filter. Then, liquid including other cells such as red blood cells or white blood cells is discharged through the filter and collection liquid is then supplied to the filter to collect lymphocytes captured by the filter (for example, see U.S. Pat. No. 6,312,950).
However, in the case of the above cell separation/collection apparatus disclosed in U.S. Pat. No. 6,312,950, only a lymphocyte is captured by an upper face of the filter. However, liquid that included the lymphocyte is discharged to the outside through the filter, thus requiring an operation to additionally separate the lymphocyte attached to the filter to collect the lymphocyte.
Thus, in the case of the cell separation/collection apparatus disclosed in U.S. Pat. No. 6,312,950, a disadvantage is caused where the separation of a lymphocyte from a filter requires an operation to change a cavity rate of the filter to a cavity rate different from that used to capture a lymphocyte and an operation to supply collection liquid to the filter, thus requiring a complicated mechanism.
It is noted that, a technique also has been known by which, when a measurement target cell has a smaller diameter than those of other cells, sample liquid including a measurement target cell is sent to a filter, and the liquid including the measurement target cell is allowed to pass through the filter and is collected, and other cells are captured by the filter and are discharged.
However, this technique allows the measurement target cell to pass through the filter. Thus, this technique cannot be used to a case as in an epidermal cell where a measurement target cell has a larger diameter than those of other cells.